Sealing mechanisms for storage tanks



Jan. 28, 1964 A. P. GIANNINI SEALING MECHANISMS FOR STORAGE TANKS 3Sheets-Sheet 1 Filed June 8, 1962 FIG./

INVENTOR.

ANTHONY R G/ANN/N/ Jan. 28, 1964 A. P. GIANNlNl 3,119,511

SEALING MECHANISMS FOR STORAGE TANKS Filed June 8. 1962 3 Sheets-Sheet 2OIL LEVEL l INVENTOR. M ANTHONY P. GIANN/N/ QWC W40) ATTYS.

Jan. 28, 1964 A. P. GIANNINI I 3,119,511

SEALING MECHANISMS FOR STORAGE TANKS Filed June 8, 1962 3 Sheets-Sheet 5im T I 0'7/4 ATTYS.

United States Patent 3,119,511 SEALING MECHANISMS FGR STGRAGE TANKSAnthony P. Giannini, Chicago Heights, 111., assignor to General AmericanTransportation Corporation, Chicago, 111., a corporation of New YorkFiled inns 8, 1962, Ser. No. 251,186 Claims. (Cl. 22fl26) The presentinvention relates to sealing mechanisms for storage tanks for petroleumproducts, or the like, and more particularly to such a storage tank ofthe type having an upstanding substantially cylindrical side wall andprovided with a floating roof carrying the sealing mechanism with itarranged in sliding and sealing engagement with the side wall, therebyto minimize evaporation of the stored petroleum products from thestorage tank and to protect the same from the elements of the weather.

It is a general object of the invention to provide a sealing mechanismof the type noted, that is of improved and simplified construction andarrangement.

Another object of the invention is to provide a sealing mechanism of thetype noted, wherein constant and adequate surface contact is maintainedby the sealing mechanism with the inner surface of the side wall of thetank, notwithstanding substantial irregularities in the side wall.

Another object of the invention is to provide a sealing mechanism of thetype noted that is exceedingly versatile in adaptation to such afloating roof, whereby the same may be readily installed upon a newfloating root incident to constructing a new storage tank, or upon anold floating roof incident to renovating an old storage tank.

A further object of the invention is to provide in a tank for storingliquids, such as petroleum products, ineluding upstanding substantiallycylindrical wall structure spaced radially inwardly from the tank sidewall and defining a substantially annular space therebetween, improvedsealing mechanism for the annular space comprising a substantiallyannular hermetically sealed casing arranged in the annular space, theupper portion of the casing being attached to the roof so that it ismovable therewith with respect to the tank side wall, the casing beingof hollow tubular configuration and formed of flexible nonmetallicsheet-like material that is impervious to the constituents of petroleumproducts and to water and to air, the casing including annular inner andouter side walls arranged in opposing spaced apart relation and alsoannular bottom and top walls arranged in opposed spacedapart relation,the casing inner side wall being disposed in engagement and fixed sealedrelation with the wall structure and the casing outer side wall beingdisposed in engagement and sliding sealed relation with the tank sidewall, the casing bottom wall being submerged in the stored liquid andthe casing top wall being disposed well above the level of the storedliquid, a substantially annular body of self-supporting resilientmaterial of cellular structure enclosed by the casing and extendingbetween the casing inner and outer side walls and constituting aresilient cushion to urge the casing inner side wall into firm sealedrelation with the wall structure and to urge the casing outer side wallinto fir-m sealed relation with the tank side wall during both verticalmovements and sidewise movements of the roof with respect to the tankside wall, and a plurality of circumferentially spaced-apart strap-loopdevices acting between the casing and the wall structure for positivelypreventing the casing from riding-up the tank side wall and out of theannular space during downward movement of the roof with respect to thetank side wall.

A still further object of the invention is to provide a sealingmechanism of the type described, wherein each of the strap-loop devicesincludes a flexible strap element that is resistant to the constituentsof petroleum products and ice to water and to air, the lower portion ofthe strap element being attached to the lower portion of the casing andthe upper portion of the strap element being attached to the upperportion of the wall structure, and a loop element carried by the lowerportion of the wall structure and receiving the intermediate portion ofthe strap element and drawing the same taut between the lower and upperportions thereof, whereby a first section of the strap element extendsbetween the lower portion of the casing and the loop element and asecond section of the strap element extend-s between the loop elementand the upper portion of the wall structure, and whereby the secondsection of the strap element is arranged between the wall structure andthe casing inner side wall. 7

Further features of the invention pertain to the particular arrangementof the elements of the sealing mechanism; whereby the above-outlined andadditional operating features thereof are attained.

The invention, both as to its organization and method of operation,together with further objects and advantages thereof, will best beunderstood by reference to the following specification, taken inconnection with the ac companying drawings, in which:

FIGURE 1 is a top perspective view, partly broken away, of a tank forstoring liquids, such as petroleum products, and provided with afloating roof petroleum products, and provided with'a floating roofcarrying sealing mechanism embodying the present invention;

FIG. 2 is an enlarged fragmentary top perspective view of a portion ofthe side wall of the storage tank and an adjacent portion of thefloating roof carrying the sealing mechanism mentioned, this view beingtaken generally in the direction of the arrows along the line 22 in FIG.1;

FIG. 3 is an enlarged fragmentary plan View of the top of the tank,illustrating weather hood mechanism carried by the top of the floatingroof and projecting over the sealing mechanism mentioned;

FIG. 4 is an enlarged vertical sectional View of the sealing mechanism,taken in the direction of the arrows along the line 4-4 of FIG. 3;

FIG. 5 is a greatly enlarged vertical sectional view of the upperportion of the sealing mechanism, as shown in FIG. 4; and

FIG. 6 is another enlarged vertical sectional view of the sealingmechanism, similar to FIG. 4, and illustrating the manner in which thestrap-loop devices incorporated in the sealing mechanism are employed inlocating the position of the sealing mechanism upon the adjacentupstanding substantially cylindrical wall structure of the floating roofand in surrounding relation therewith.

Referring now to FIGS. 1 and 2 of the drawings, there is illustrated atank 10 for storing liquids, such as petroleum products, that includesan upstanding substantially cylindrical side wall 11 and provided withan open top bounded by an annular rim 12 and carrying an annular catwalk13 arranged about the upper portion thereof and disposed adjacent to andbelow the annular rim 12. Also, an annular roof 29 is arranged in thetank 10 in floating relation with respect to the stored liquid; wherebythe floating roof 2% rises and falls with respect to the side wall :110f the tank 10 in accordance with the head of the body of liquid storedtherein. As illustrated, the floating roof 2t) comprises inner structuredefining a centrally disposed annular pontoon 21, enter structuredefining an outer annular pontoon 22, and connecting structure definingan annular deck 23 disposed between the pontoons 21 and 22. As bestshown in FIGS. 2 and 4, the outer annular pontoon 22 comprisesupstanding substantially cylindrical wall structure 24 spaced radiallyinwardly from the tank side wall 11 and defining an annular space 25therebetween.

Arranged within the annular space 25 and carried by thefioating roof 20,is sealing mechanism 30 embodying the features of the present invention.As indicated in FIG. 4, when the roof 26 is floating upon the body ofliquid stored in the tank 10, the lower portion of the outer pontoon 22is submerged therein, the normal liquid level in the tank It} beingindicated by the broken line 26. The sealing mechanism 39 essentiallycomprises, as best shown in FIGS. 2, 4 and 5, a hollow tubularhermetically sealed casing 31 formed of flexible nonmetallic sheetlikematerial that is impervious to the constituents of petroleum productsand to Water and to air, the casing 31 including an annular inner sidewall 32 secured in fixed sealed engagement with the wall structure 24adjacent to the upper portion thereof, an annular outer side wall 33disposed in sliding sealed engagement with the tank side wall 11, anannular bottom wall 34 submerged in the stored liquid, and an annulartop wall 35 disposed above the liquid level. In the arrangement, thecasing 31 is formed of flexible sheet-like synthetic organic resinousmaterial; and preferably, this sheet material comprises the syntheticrubber composition sold commercially under the name Ensolite Type F bythe US. Rubber Company. Specifically, this synthetic rubber compositioncomprises nitrile rubber modified by polyvinyl chloride resin, thecomposition containing by weight about 75% of the nitrile rubber; and,in turn, the nitrile rubber comprises copolymers of butadieneacrylonitrile, the butadiene content ranging from about 55% to 80% byweight. This synthetic rubber composition is of the closedrcell type andis of tough cellular construction having the gen eral apeparance offoamed rubber. Moreover, the corn position is capable of vulcanizationin a manner entirely similar .to that of natural rubber, but showssuperior resistance to oils and solvents in general, and withstands theeffects of aging, abrasion and heat much better than natural rubber.Also, this synthetic rubber composition is superior to natural rubberwith respect to minimizing swelling thereof in the presence of petroleumproducts.

Also, the sealing mechanism 30 comprises an annular body or ring 36 ofresilient material that is enclosed within the casing 31, which body 36is essentially formed of synthetic organic resin of open-cell structure;and preferably, the body 36 is formed of foamed polyurethane. In orderto predetermine the compression of the body 36 of resilient material, aplurality of radially spaced-apart annular rows of upstanding openings37 are formed therein, the individual openings 37 in each row beingarranged in .circumferentially spaced-apart relation. In thearrangement, the body 36 occupies a major fraction of the volume of thecasing 31; and specifically, the body 36 may occupy about 80% of thetotal volume of the casing 31. Furthermore, the total porosity of thebody 36 is about 80%; whereby the. total gas space within the casing 31is about 85% of the total volume thereof. In the arrangement, the body36 extends between the inner upstanding annular wall portion 32 and theouter upstanding annular wall portion 33 and serves as a resilientcushion located therebetwcen, the inner and outer upstanding faces ofthe body 36 being suitably cemented to the adjacent faces of the wallportions 32 and 33 by intervening layers of cement, not shown, wherebythe opposed inner and outer upstanding faces of the body 36 areintimately united by the cement layers mentioned respectively to theadjacent surfaces of the wall portions 32 and 33 of the casing 31. Onthe other hand, the bot-tom face of the body 36 is not secured to theadjacent bottom wall portion 34 of the casing 31, so that the bottomwall portion 34 is free to move with respect to the bottom face of thebody 36; and likewise, the upper face of the body 36 is spaced Wellbelow the adjacent top wall portion 35 of the casing 31. Accordingly,the principal gas pocket in the casing 31 is formed above the body 36and directly communicating with the upper ends of the upstandingopenings 37 provided through the body 36. The principal gas pocketmentioned defined in the casing 31 is ordinarily filled with air, which,of course, permeates the structure of the porous body 36 since it is ofopen-cell structure, as previously noted.

The sealing mechanism 30 is retained in its mounted position upon theadjacent outer surface of the upstanding substantially cylindrical wallstructure 24 of the floating roof 2t and within the annular space 25 andin surrounding relation with the outer pontoon 22 by an arrangementincluding an upstanding annular ring 38 rigidly secured to the extremeupper end of the upstanding wall structure 24, as by welding, as bestshown in FIG. 5; and to this annular ring 38 the sealing mechanism 3b isdetachably secured by an arrangement including another surroundingannular ring 39 and a series of circumferentially spaced-apart bolts 40provided with cooperating nuts 41. In the arrangement, the extreme upperend of the inner wall 32 and the extreme upper end of the top wall 35 ofthe casing 31 are disposed in facing engagement with each other andpositioned between the clamping rings 38 and 39 and held securelytogether in clamped relation therebetween so that the hollow casing 31is hermetically sealed, as previously noted.

Also, the sealing mechanism 3% is retained in place by an arrangementincluding a plurality of circumferentially spaced-apart strap-loopdevices 50 acting between the casing 31 and the upstanding Wallstructure 24 of the outer pontoon 22. As best illustrated in FIGS. 4, 5and 6, each of the strap-loop devices 59 includes a reinforcing pad 51,a first flexible strap element 52, a second flexible strap element 53and a loop element 54. In the arrangement, the reinforcing pad 51 andeach of the strap elements 52 and 53 are formed of a material that isresistant to the constituents of petroleum products and to water and toair and may essentially comprise a rubberized woven textile fabric,such, for example, as rubberized canvas, While the loop-like element 54may be formed of steel. More particularly, the reinforcing pad 51 issecurely attached to the lower inner portion of the casing 31; while theloop-like element 54 is securely attached, as by welding, not shown, tothe lower portion of the upstanding wall stucture 2d at a locationpositioned below the bottom wall 34 of the casing 31. Specifically, thereinforcing pad 51 includes an upstanding inner portion 51a positionedover the casing inner side wall 32 and securely affixed thereto, as bystitching, as indicated at 51b; and an outwardly directed outer portion51c positioned over the casing bottom wall 34 and securely aflixedthereto, as by stitching, as indicated at 51d. The lower end of thefirst strap element 52 is securely attached to the inner portion 51a ofthe reinforcing pad 51, as by stitching, as indicated at 52a; andlikewise, the lower end of the second strap element 53 is securelyattached to the outer portion 51c of the reinforcing paid 51, as bystitching, as indicated at 53a. The intermediate portions of the strapelements 52 and 53 are threaded through the loop element 54 and extendupwardly between the casing inner side wall 32 and the upstanding wallstructure 24. The upper ends of the strap elements 52 and 53 extendbetween the outer surface of the clamping ring 38 and the inner surfaceof the extreme top end of the casing inner side wall 32 and are retainedin place by the clamping bolt 40 extending through cooperating holesrespectively provided in the upper ends of the strap elements 52 and 53.

Preferably, the first and second strap elements 52 and 53 are formedwith a single run of material folded upon itself with the fold 55 of thematerial connecting together the extreme upper ends of the strapelements 52 and 53, as best illustrated in FIGS. 5 and 6. Accordingly, afirst lower section of the first strap element 52 extends between theinner portion 51a of the reinforcing pad 51 and the loop element 54 anda first lower section of the second strap element 53 extends between theouter portion 510 of the reinforcing pad 51 and the loop ele- Inent 54,second upper sections of the strap elements 52 and 53 extend upwardlybetween the loop element 54 and the clamping ring 38 carried at the topof the upstanding wall structure 24, and the fold 55 connecting togetherthe extreme upper ends of the strap elements 52 and 53 is disposed abovethe clamping arrangement including the clamping rings 38 and 39 and thecooperating clamping bolt 40, as best illustrated in FIG. 5.

In view of the foregoing, it wil be understood that as the floating roof2%? rises and falls in the tank 10, it carries therewith the sealingmechanism 30 filling a substantial portion of the annular space 25between the upstanding wall structure 24 of the outer pontoon 22 and thecylindrical side wall 11 of the tank and maintaining a sealtherebetween, so as to minimize the evaporation of petroleum productsfrom the body thereof stored in the tank 10. Moreover, the strap-loopdevices 50 prevent the hollow casing 31 of the sealing mechanism 30 fromrolling upwardly with respect to the upstanding wall structure 24incident to downward movement of the floating roof with respect to thetank side wall 11 and maintain the inner annular wall portion 32 of thehollow casing 31 firmly pressed into fixed sealed engage ment withadjacent upstanding wall structure 24 of the outer pontoon 22. Also, theresilient body 37, sealed within the hollow casing 21 of the sealingmechanism 30, maintains the outer annular wall portion 33 in firmsliding sealed engagement with the tank side wall 11 in the verticalmovement of the floating roof 2% with re spect to the tank side wall 11.Further, the securing of the inner and outer wall portions 32 and 33 ofthe hollow casing 31 to the adjacent surfaces or faces of the body 36prevents respective slippages therebetween incident to the verticalmovements of the floating roof 20 with respect to the tank side wall 11.Furthermore, the resiliency of the body 36 maintains firm compressionbetween the opposed wall portions 32 and 33 of the hollow casing 31,notwithstanding substantial sidewise movements of the floating roof 2%)with respect to the tank side wall 11, that occur particularly duringsubstantial wind storms. Also, it will be understood that the porouscharacter of the body 36 accommodates free pumping action of the airhermetically sealed within the casing 31 between the principal gaspocket therein and the structure of the body 36 incident to expansion orcontraction of a segment of the hollow casing 31 as a consequence ofside wise movements of the floating roof 20 with respect to the tankside wall 11. In the arrangement, the bottom wall portion 34 of thehollow casing 31 is maintained in submerged relation with respect to theliquid stored in the tank 10, and regardless of the vertical movementsand the sidewise movements of the floating roof 20 with respect to thetank side wall 11, thereby to prevent the formation of a gas pocket inthe lower portion of the annular space disposed below the bottom wallportion 34 of the hollow casing 31, so as to minimize the fire hazardinherent in the storage of petroleum products.

In installing the sealing mechanism in the annular space 25 disposedbetween the tank side wall 11 and the upstanding wall structure 24 ofthe outer pontoon 22, the annular casing 31 is prefabricated enclosingthe resilient body 36 and carrying the circumferentially spaced-apartreinforcing pads 51 that, in turn, carry the corresponding pairs ofstrap elements 52, 53. The floating roof 20 is supported within the tank10 somewhat above the bottom wall thereof and spaced radially inwardlywith respect to the tank side wall 11. The casing 31 of the sealingmechanism 30 is placed in the annular space defined between theupstanding wall structure 24 of the outer pontoon 22 and the tank sidewall 11. The fold or handle portions 55 of the strap elements 52, 53 arethreaded upwardly through the adjacent loop elements 54 carried by thelower portion of the upstanding wall structure 24 of the outer pontoon22. The loop or handle portions 55 of the strap elements 52, 53 are thenpulled upwardly between the casing inner side wall 32 and the upstandingwall srtucture 24 so as to cause the casing 31 to ride downwardly andinwardly into proper supported position with respect to the outersurface of the upstanding wall structure 24. In the arrangement, theholes that are provided through the outer end portions of each pair ofthe strap elements 52 and 53 are prelocated so that these holesmentioned fall in alignment with the adjacent hole formed in the upperclamping ring 38, when the strap elements 52, 53 are pulled tautlocating the casing 31 in proper position with respect to the adjacentouter surface of the upstanding wall structure 24. At this time, theclamping bolt 40 may be drifted or inserted through the adjacent holeprovided in the clamping ring 38 and thence through the aligned holesprovided in the strap elements 52 and 53 through the aligned holesprovided in the upper edges of the wall elements 32 and 35 of the casing31 and through the aligned hole provided in the outer clamping ring 39;whereby the associated nut 41 may be located upon the outer threaded endof the clamping bolt 40 so as to retain together the assembly.

In view of the foregoing, it will be appreciated that the strap-loopdevices 50 not only retain the casing of the sealing mechanism 30 inproper position in the annular space 25 and secured to the upstandingwall structure 24 of the outer pontoon 22 after the final assembly hasbeen made of the sealing mechanism 30 upon the upstanding wall structure24, but these strap-loop devices 50 facilitate ready field assembly ofthe sealing mechanism 30 in the annular space 25 between the tank sidewall 11 and the upstanding wall structure 24 of the outer pontoon 22incident to installation of the sealed mechanism 30, as describedimmediately above.

Further, the floating roof 20 carries weather hood mechanism 64) that ispreferably of the construction and arrangement of that disclosed in US.Patent No. 2,997,200, granted on August 22, 1961 to Anthony P. Gianniniand Eli F. Smith; which weather hood mechanism 64 is of compositeconstruction including an annular array of a plurality individualplate-like hood segments 61. The composite weather hood mechanism 60 ispitched radially upwardly and outwardly from the floating roof 20 andover the upper portion of the upstanding wall structure 24 of the outerpontoon 22 and over the annular space 25 in which the sealing mechanism30 is arranged and with the outer circumferential edge thereof disposedadjacent to the tank side wall 11 and with the inner circumferentialedge thereof disposed radially inwardly of the upstanding wall structure24. More particularly, a plurality of circumferentially spaced-apart andupwardly directed brackets 62 are carried by the annular clamping ring38 just above the top of the upstanding wall structure 24 and receivethe inner edges of the hood segments 61 mounting the same for individualvertical pivotal movements with respect thereto, as best shown in FIG.4. Specifically, each of the brackets 62 may be of generally Z-shapedconfiguration, including an arm 63 disposed in direct engagement withthe adjacent inner surface of the annular clamping ring 38 and securedin place by the adjacent clamping bolt 40 that is employed for thepurpose of securing in place the sealing mechanism 30, as previouslyexplained.

Also, each of the brackets 62 comprises an arm 64 disposed above theadjacent upper surface of the received hood segment 61, as well as abody 65 disposed below the adjacent lower portion of the received hoodsegment 61. In the arrangement, two of the brackets 62 may be employedfor the purpose of mounting each one of the hood segments 61 upon thefloating roof 20, as illustrated in FIG. 3; and moreover, the hoodsegments 61 are detachably secured in place by a plurality of lockingpins 66 respectively carried by the brackets 62. More particularly, eachof the locking pins 66 extends through a pair of aligned holesrespectively provided in the portions 64 and 65 of the associatedbracket 62 and also through an aligned hole provided in the associatedhood segment 61 adjacent to the inner edge thereof that is receivedbetween the elements 64 and 65 of the bracket 62.

In the arrangement, the elements 64 and 65 of each of the brackets 62are disposed inwardly with respect to the annular clamping ring 38 sothat the inner edge of the received hood segment 61 overhangs thefloating roof 20 in order to accommodate shedding of rain water from thehood segments 61 onto the floating roof 20. The upper and lower elements64 and 65 of each of the brackets 62 are respectively disposed above andbelow the adjacent inner edge of the received hood segment 61, aspreviously noted, and cooperate therewith to limit the vertical pivotalmovements of the hood segment 61 through an angle disposed well abovethe horizontal and well below the vertical, thereby 'to prevent the hoodsegment 61 from being trapped between the tank side wall 11 and the wallstructure 24 incident to movement of the roof 20 sidewise into aposition of maximum clearance with respect to the tank side wall 11 andto prevent the hood segment 61 from folding back onto the top of theroof 20 incident to movement of the roof 20 sidewise into a position ofminimum clearance with respect to the tank side wall 11. Accordingly, itwill be understood that the mounting arrangement including the brackets62 limits the vertical pivotal movements of the hood segments 61; whilethe removable locking pins 66 accommodate ready removal of theindividual hood segments 61 from the composite weather hood 60 for thepurpose of inspection and repair of the sealing mechanism 39 disposedtherebelow.

In the arrangement of the weather hood segments 61 in the compositeweather hood 60, the end edges thereof are disposed in overlappedsliding relation to render the composite weather hood continuous whilepreserving relative vertical pivotal movements of the individual hoodsegments 61 about the inner edges thereof upon the brackets 62; and froma practical standpoint, each of the hood segments 61 may besubstantially rectangular, although it is preferable that the outer edgethereof be slightly contoured so as substantially to conform to thecorressponding arcuate segment of the adjacent portion of the tank sidewall 11, as clearly shown in FIG. 3. Further, the composite weather hood60 comprises a composite bumper ring in the form of an annular array ofa plurality of individual bumper segments 71 respectively carried by theouter edges of the individual hood segments 61 and disposed in slidingengagement with the tank side wall 11, as best shown in FIGS. 3 and 4.More particularly, each of the bumper segments 71 includes asubstantially tubular flexible outer casing 7-2 secured to the carryinghood segment 61 in embracing relation with the outer edge thereof anddisposed in sliding engagement with the adjacent portion of the tankside wall 11, as shown in FIG. 4. Also each of the bumper segments 71includes a yieldable inner element 73 enclosed by the outer casing 72and imparting resiliency thereto so as to cause the outer casing 72 toconform to the engaged adjacent portion of the tank side wall 11. In thearrangement, the inner element 73 may have a tubular configuration thatis slit longitudina'lly to receive the adjacent outer edge of thecarrying hood segment 61 and the casing 72 is tightly wrapped around theinner element 73, the inner edges of the casing 72 being suitablysecured in place upon the ad jacent outer portion of the carrying hoodsegment 61 by an arrangement including upper and lower substantiallyarcuate clamping members 74 and 75 secured in place by a series ofm'vets 76, or the like, as best shown in FIG. 4. This arrangement of theinner element 73 within the outer casing 72 renders the bumper segment71 as a whole yieldable with respect to the adjacent portion of the tankside wall 11; and also the inner position of the inner element 73 withinthe casing 72 prevents knifing of the outer casing 72 by the extremeouter edge 8 of the hood segment 61 against the adjacent portion of thetank side wall 11, thereby contributing to a long useful life of thebumper segment 71.

As best shown in FIG. 3 and in conjunction with the entrally disposedhood segment 61 there illustrated, the left-hand end of the casing 72terminates adjacent to the associated left-hand end of the centrallydisposed hood segment 61, while the right-hand end of the casing 72projects circumferentially somewhat beyond the adjacent right-hand endof the centrally disposed hood segment 61, whereby the right-hand end ofthe casing 72 of the centrally disposed bumper segment 71 overlaps intelescopic relation the left-hand end of the casing 72 of the adjacentright-hand bumper segment 71; and whereby the right-hand end of thecasing 72 of the left-hand bumper segment 71 overlaps in telescopicrelation the left-hand end of the casing 72 of the centrally disposedbumper segment 71. The above-described arrangement of the adjacent endsof the individual bumper segments 71 in the composite bumper ringrendering the same continuous, 'while preserving relatively verticalpivotal movements of the individual bumper segments 71 with therespective carrying ones of the individual hood segments 61, whereby thecontinuity of the composite weather hood and of the composite bumperring are preserved, notwithstanding vertical p-ivotal movements of theindividual hood segments '61 and of the individual bumper segments 71incident to sidewise movements of the roof 20 with respect to the tankside wall 11.

In the construction of the bumper ring segment 71, the inner resilientelement 73 may comprise an appropriate length of rubber hose or othersuitable resilient material, while the outer casing 72 is formed of asuitable sealing fabric. For example, the casing 72 may essentiallycomprise a textile sheet that is impregnated with synthetic onganicresinou material, such, for example, as the previously mentionedsynthetic rubber composition sold commercially under the trade nameEnsolite Type F.

In view of the foregoing, it will be understood that in the compositeweather hood, the continuity of both the hood segments 61 in the annulararray thereof and the continuity of the bumper ring segments 71 in theannular array thereof are preserved, notwithstanding vertical pivotalmovements of the individual hood segments 61 upon the cooperating pairsof brackets 62 incident to sidewise movements of the floating roof 20with respect to the side wall 11 of. the tank 10. Of course, it will beappreciated that the composite weather hood mechanism 69 carrying thecomposite bumper ring in sliding engagement with the interior surface ofthe tank side wall 11 protects the annular space 25 containing thesealing mechanism 30 against the entry thereinto of rain and otherelements of weather, as well as foreign materials; and moreover, thecomposite weather hood mechanism 60 insures that rain is shed downwardlythereover onto the underlying peripheral edge portion of the floatingroof 20 and thus drained away from the protected annular space 25. Themechanism for draining the rain water from the floating roof 20 to theexterior is not disclosed in detail since this draining mechanism may beof any suitable conventional arrangement.

'In view of the foregoing, it is apparent that there has been providedin a tank for storing liquids, such as petroleum products, and includinga floating roof, an improved sealing mechanism for the annular spacedisposed between the upstanding side wall of the tank and the upstandingWall structure of the floating roof, wherein the sealing mechanism is ofthe tubular seal type and comprises a plurality of circumferentiallyspaced-apart strap-loop devices of improved construction and arrangementacting between the casing of the tubular seal and the wall structure ofthe floating roof for positively preventing the casing from ridingup thetank side wall and out of the annular space during downward movement ofp the floating roof with respect to the tank side wall; which strap loopdevices are also useful in effecting easy assembly and installation ofthe sealing mechanism upon the adjacent upstanding annular wallstructure of the floating roof.

While there has been described what is at present con sidered to be thepreferred embodiment of the invention, it will be understood thatvarious modifications may be made therein, and it is intended to coverin the appended claims all such modifications as fall within the truespirit and scope of the invention.

What is claimed is:

1. In a tank for storing liquids, such as petroleum products, includingan upstanding substantially cylindrical side wall, and a floating roofarranged in said tank and including upstanding substantially cylindricalwall structure spaced radially inwardly from said tank side wall anddefining a substantially annular space therebetween; sealing mechanismfor said annular space comprising a substantially annular hermeticallysealed casing arranged in said annuler space, means for attaching theupper portion of said casing to said roof so that it is movabletherewith with respect to said tank side wall, said casing being ofhollow tubular configuration and formed of flexible nonmetallicsheet-like material that is impervious to the constituents of petroluemproducts and to water and to air, said casing including annular innerand outer side walls arranged in opposing spaced-apart relation and alsoannular bottom and top walls arranged in opposing spacedapart relation,said casing inner side wall being disposed in engagement and fixedsealed relation with said wall structure and said casing outer side wallbeing disposed in engagement and sliding sealed relation with said tankside wall, said casing bottom wall being submerged in the stored liquidand said casing top wall being disposed well above the level of thestored liquid, a substantially annular body of self-supporting resilientmaterial of cellular structure enclosed by said casing and extendingbetween said casing inner and outer side walls and constituting aresilient cushion to urge said casing inner side wall into firm sealedrelation with said wall structure and to urge said casing outer sidewall into firm sealed relation with said tank side wall during bothvertical movements and sidewise movements of said roof with respect tosaid tank side wall, and means including a plurality ofcircumferentially spaced-apart strap-loop devices acting between saidcasing and said wall structure for positively preventing said casingfrom riding-up said tank side wall and out of said annular space duringdownward movement of said roof with respect to said tank side wall; eachof said strap-loop devices including a flexible strap element that isresistant to the constituents of petroleum prod nets and to water and toair, the lower portion of said strap element being attached to the lowerportion of said casing and the upper portion of said strap element beingattached to the upper portion of said wall structure, and a loop elementcarried by the lower portion of said wall structure and receiving theintermediate portion of said strap element and drawing the same tautbetween the lower and upper portions thereof, whereby a first section ofsaid strap element extends between the lower portion of said casing andsaid loop element and a second section of said strap element extendsbetween said loop element and the upper portion of said wall structure,and whereby the second section of said strap element is arranged betweensaid wall structure and said casing inner side wall.

2. In a tank for storing liquids, such as petroleum products, includingan upstanding substantially cylindrical side wall, and a floating roofarranged in said tank and including upstanding substantially cylindricalwall structure spaced radially inwardly from said tank side wall anddefining a substantially annular space therebetween; sealing mechanismfor said annular space comprising a substantially annular hermeticallysealed casing arranged in said annular space, means including aplurality of circumferentially spaced-apart fastening elements carriedby the upper portion of said wall structure for attaching the upperportion of said casing thereto so that said casing is movable with saidroof with respect to said tank side wall, said casing being of hollowtubular configuration and formed of flexible nonmetallic sheet-likematerial that is impervious to the constituents of petroleum productsand to water and to air, said casing including annular inner and outerside walls arranged in opposing spaced-apart relation and also annularbottom and top walls arranged in opposing spaced-apart relation, saidcasing inner side wall being disposed in engagement and fixed sealedrelation with said wall structure and said casing outer side wall beingdisposed in engagement and sliding sealed relation with said tank sideWall, said casing bottom wall being submerged in the stored liquid andsaid casing top wall being disposed well above the level of the storedliquid, a substantially annular body of self-supporting resilientmaterial of cellular structure enclosed by said casing and extendingbetween said casing inner and outer side walls and constituting aresilient cushion to urge said casing inner side Wall into firm sealedrelation with said wall structure and to urge said casing outer sidewall into firm sealed relation with said tank side wall during bothvertical movements and sidewise movements of said roof with respect tosaid tank side wall, and means including a plurality ofcircumferentially spaced-apart strap-loop devices acting between saidcasing and said wall structure for positively preventing said casingfrom riding-up said tank side wall and out of said annular space duringdownward movement of said roof with respect to said tank side wall; eachof said straploop devices including a flexible strap element that isresistant to the constituents of petroleum products and to water and toair, means for attaching the lower portion of said strap element to thelower portion of said casing, means including one of said fasteningelements for attaching the upper portion of said strap element to theupper portion of said wall structure, and a loop element carried by thelower portion of said wall structure and receiving the intermediateportion of said strap element and drawing the same taut between thelower and upper portions thereof, whereby a first section of said strapelement extends between the lower portion of said casing and said loopelement and a second section of said strap element extends between saidloop element and the upper portion of said wall structure, and wherebythe second section of said strap element is arranged between said wallstructure and said casing inner side wall.

3. The sealing mechanism set forth in claim 1, wherein said strapelement essentially comprises a woven fabric.

4. In a tank for storing liquids, such as petroleum products, includingan upstanding substantially cylindrical side wall, and a floating roofarranged in said tank and including upstanding substantially cylindricalwall structure spaced radially inwardly from said tank side wall anddefining a substantially annular space therebetween; sealing mechanismfor said annular space comprising a substantially annular hermeticallysealed casing arranged in said annular space, means for attaching theupper portion of said casing to said roof so that it is movabletherewith with respect to said tank side wall, said casing being ofhollow tubular configuration and formed of flexible nonmetallicsheet-like material that is impervious to the constituents of petroleumproducts and to water and to air, said casing including annular innerand outer side Walls arranged in opposing spaced-apart relation and alsoannular bottom and top Walls arranged in opposing spaced-apart relation,said casing inner side wall being disposed in engagement and fixedsealed relation with said wall structure and said casing outer side wallbeing disposed in engagement and sliding sealed relation with said tankside wall, said casing bottom wall being submerged in the stored liquidand said casing top wall being disposed well above the level of thestored liquid, a substantially annular body of self-supporting resilientmaterial of cellular structure enclosed by said casing and extendingbetween said casing inner and outer side walls and constituting aresilient cushion to urge said casing inner side wall into firm sealedrelation with said wall structure and to urge said casing outer sidewall into finn sealed relation with said tank side wall during bothvertical movements and sidewise movements of said roof with respect tosaid tank side wall, and means including a plurality ofcircumferentially spaced-apart strap-loop devices acting between saidcasing and said wall structure for positively preventing said casingfrom riding up said tank side wall and out of said annular space duringdownward movement of said roof with respect to said tank side wall; eachof said strap-loop devices including a reinforcing pad that is resistantto the constituents of petroleum products and to water and to air, saidreinforcing pad being attached to the lower portion of said casing withan inner portion of said reinforcingpad positioned over said casinginner side wall and with an outer portion of said reinforcing padpositioned over said casing bottom wall, first and second flexible strapelements that are resistant to the constituents of petroleum productsand to water and to air, the lower end of said first strap element beingattached to the inner portion of said reinforcing pad and. the upper endof said first strap element being attached to the upper portion of saidwall structure, the lower end of said second strap eleinent beingattached to the outer portion of said reinforcing pad and the upper endof said second strap element being attached to the upper portion of saidwall structure, and a loop element carried by the lower portion of saidwall structure and receiving the intermediate portions of said strapelements and drawing the same taut between the respective lower andupper ends thereof, whereby a first section of said first strap elementextends between the inner portion of said reinforcing pad and said loopelement and a first section of said second strap element extends betweenthe outer portion of said reinforcing pad and said loop element andsecond sections of said strap elements extend between said loop elementand the upper portion of said wall structure, and whereby the secondsections of said strap elements are arranged between said wall structureand said casing inner side wall.

5, The sealing mechanism set forth in claim 4, wherein said first andsecond strap elements are formed of a single run of material folded uponitself with the fold of the material connecting together the upper endsof said strap elements.

References Cited in the file of this patent UNITED STATES PATENTS3,033,413 Fino et al. May 8, 1962 3,043,468 Horner July 10, 19623,055,533 Reese et al Sept. 25, 1962 3,075,663 Reese Jan. 29, 1963FOREIGN PATENTS 834,070 Great Britain Dec. 6, 1961

1. IN A TANK FOR STORING LIQUIDS, SUCH AS PETROLEUM PRODUCTS, INCLUDINGAN UPSTANDING SUBSTANTIALLY CYLINDRICAL SIDE WALL, AND A FLOATING ROOFARRANGED IN SAID TANK AND INCLUDING UPSTANDING SUBSTANIALLY CYLINDRICALWALL STRUCTURE SPACED RADIALLY INWARDLY FROM SAID TANK SIDE WALL ANDDEFINING A SUBSTANTIALLY ANNULAR SPACE THEREBETWEEN; SEALING MECHANISMFOR SAID ANNULAR SPACE COMPRISING A SUBSTANTIALLY ANNULAR HERMETICALLYSEALED CASING ARRANGED IN SAID ANNULER SPACE, MEANS FOR ATTACHING THEUPPER PORTION OF SAID CASING TO SAID ROOF SO THAT IT IS MOVABLETHEREWITH WITH RESPECT TO SAID TANK SIDE WALL, SAID CASING BEING OFHOLLOW TUBULAR CONFIGURATION AND FORMED OF FLEXIBLE NONMETALLICSHEET-LIKE MATERIAL THAT IS IMPERVIOUS TO THE CONSTITUENTS OF PETROLEUMPRODUCTS AND TO WATER AND TO AIR, SAID CASING INCLUDING ANNULAR INNERAND OUTER SIDE WALLS ARRANGE IN OPOOSING SPACED-APART RELATION AND ALSOANNULAR BOTTOM AND TOP WALLS ARRANGED IN OPPOSING SPACEDAPART RELATION,SAID CASING INNER SIDE WALL BEING DISPOSED IN ENGAGEMENT AND FIXEDSEALED RELATION WITH SAID WALL STRUCTURE AND SAID CASING OUTER SIDE WALLBEING DISPOSED IN ENGAGEMENT AND SLIDING SEALED RELATION WITH SAID TANKSIDE WALL, SAID CASING BOTTOM WALL BEING SUBMERGED IN THE STORED LIQUIDAND SID CASING TOP WALL BEING DISPOSED WELL ABOVE THE LEVEL OF THESTORED LIQUID, A SUBSTANTIALLY ANNULAR BODY OF SELF-SUPPORTING RESILIENTMATERIAL OF CELLULAR STRUCTURE ENCLOSED BY SAID CASING AND EXTENDINGBWTWEEN SAID CASING INNER AND OUTER SIDE WALLS AND CONSTITUTING ARESILIENT CUSHION TO URGE SAID CASING INNER SIDE ALL INTO FIRM SEALEDRELATION WITH SAID WALL STRUCTURE AND TO URGE SAID CASING OUTER SIDEWALL INTO FRIM SEALED RELATION WITH SAID TANK SIDE ALL DURING BOTHVERTICAL MOVEMENTS AND SIDEWISE MOVEMENTS OF SAID ROOF WITH RESPECT TOSAID TANK SIDE WALL, AND MEANS INCLUDING A PLURALITY OFCIRCUMFERENTIALLY SPACED-APART STRAP-LOOP DEVICES ACTING BETWEEN SAIDCASING AND SAID WALL STRUCTURE FOR POSITVELY PREVENTING SAID CASING FROMRIDING-UP SAID TANK SIDE WALL AND OUT OF SAID ANNULAR SPACE DURINGDOWNWARD MOVEMENT OF SAID ROOF WITH RESPECT TO SAID TANK SIDE WALL; EACHOF SAID STRAP-LOOPDEVICES INCLUDING A FLEXIBLE STRAP ELEMENT THAT ISRESISTANT TO THE CONSTITUENTS OF PETROLEUM PRODUCTS AND TO WATER AND TOAIR, THE LOWER PORTION OF SAID STRAP ELEMENT BEING ATTACHED TO THE LOWERPORTION OF SAID CASING AND THE UPPER PORTION OF SAID STRAP ELEMENT BEINGATTACHED TO THE UPPER PORTION OF SAID WALL STRUCURE, AND A LOOP ELEMENTCARRIED BY THE LOWER PORTION OF SAID WALL STRUCTURE AND RECEIVING THEINTERMEDIATE PORTION OF SAID STRAP ELEMENT AND DRAWING THE SAME TAUTBETWEEN THE LOWER AND UPPER PORTIONS THEREOF, WHEREBY A FIRST SECTION OFSAID STRAP ELEMENT EXTENDS BETWEEN THE LOWER PORTION OF SAID CASING ANDSAID LOOP ELEMENT AND A SECOND SECTION OF SAID STRAP ELEMENT EXTENDSBETWEEN SAID LOOP ELEMENT AND THE UPPER PORTION OF SAID WALL STRUCTURE,AND WHEREBY THE SECOND SECTION OF SAID STRAP ELEMENT IS ARRANGED BETWEENSAID WALL STRUCTURE AND SAID CASING INNER SIDE WALL.